The present invention relates to a breaker apparatus to be used for switching the power cable connected to the battery or the like of the automotive vehicle between the conduction state and the out-of-conduction state.
In the Japanese Patent Application No. Hei10-47920 filed by the present applicant, as shown in FIG. 13, there is shown a breaker apparatus 1 and fuse 4 being provided separately in the midsection of the power cable of the electric vehicle.
On the other hand, in the Unexamined Japanese Patent Application Publication No. Hei9-223439, as shown in FIG. 14, a breaker apparatus 3 provided with a fuse 4 accommodated therein. The breaker -apparatus 3 accommodates a fuse 4 within the case body 5A, and is provided with two cylindrical fixed electrodes 2, 2 projecting upwardly from the bottom of the case 5A. The cover 5B for closing the upper opening of the case body 5A is formed with a pair of through holes 6, 6 corresponding to the fixed electrodes 2, 2. When cylindrical leg portions 8, 8 provided on the movable electrode 7 are inserted into these holes 6, 6, the fixed-electrodes 2, 2 and legs 8, 8 are fitted, so that the fixed electrodes 2, 2 are brought into conduction, whereby the cable e is switched from the out-of-conduction state into the conduction state.
Both breaker apparatuses 1, 3 described above have both an advantage and a disadvantage. In other word, the breaker apparatus 1 (See FIG. 13) has an advantage in that since it is separate from the fuse 4, it can be downsized in comparison with the apparatus having a fuse integrated therein, while it has a disadvantage in that close attention must be paid to verification whether the breaker apparatus 1 is in OFF-state when the operator have to touch the fuse, for example, for replacing the fuse, because the fuse 4 may be exposed with the breaker apparatus 1 in ON-state.
On the other hand, the latter case (See FIG. 14) has an advantage in that verification described above is not necessary because replacement of the fuse cannot be performed without disangaging the movable electrode to turn the breaker apparatus 3 OFF, thus the breaker apparatus is always in OFF state when replacing the fuse. However, the breaker apparatus 3 has a structure having two fixed electrodes 2, 2 separately in upright position, it is difficult to satisfy the requirement of downsizing. In addition, operation is not easy because the movable electrodes have to be passed through the cover 5B at two positions in order to connect the movable electrode 7 and the fixed electrode 2.
With such a circumstances in view, it is an object of the present invention to provide a breaker apparatus being able to be downsized, being brought out of conduction without fail when replacing the fuse, and being easy to operate.
A breaker apparatus according to the first aspect of the invention comprises a projecting wall standing upright from the base of the breaker body, a pair of plate-shaped fixed electrodes laid on the front and back surfaces of the projecting wall, a recessed plug to be fitted on the projecting wall, a U-shaped movable electrode to be stored in the plug for bringing the both fixed electrodes into conduction by clamping the projecting wall on its front and back surfaces, a fuse storage section for storing the fuse connected to one of fixed electrodes, a cover for covering the opening of the fuse storage section and being fittable to the surrounding wall, an engaging surface formed on the plug and facing in the fitting direction of the plug, and a cover motion stopper provided on the cover for engaging with the engaging surface of the plug with the plug fitted to the projecting wall.
In the structure according to the first aspect of the invention, since a pair of fixed electrodes are located at one point by laying them on the front and back surfaces of the projecting wall, the space around both fixed electrodes can be shared and thus the breaker apparatus can be downsized. When the plug is fitted to the projecting wall, the projecting wall is interposed between the movable electrodes stored in the plug so that both fixed electrodes are brought into conduction. At this time, since just a single plug is required to be mounted, mounting operation can be carried out easier than the case of conventional one that requires two plugs. When the plug is fitted onto the projecting wall, the cover motion stopper provided on the cover for covering the fuse storage section engages with the engaging surface provided on the plug. Therefore, the cover cannot be removed unless the plug is pulled out, in other word, it is ensured that the plug is removed and brought out of conduction when replacing the fuse.
The invention according to the second aspect is a breaker apparatus as set forth in the first aspect, wherein the engaging surface is disposed on the plug on the side of the tip in the fitting direction, and the cover motion stopper is disposed on the lower end of the vertical wall suspending from the top portion of the cover along the side surface of the plug and formed in the shaped of a projecting strip overhanging from the lower end of the vertical wall so as to lie along the engaging surface of the plug.
According to the second aspect of the invention, since the cover motion stopper engages with the engaging surface provided on the distal end of the plug in the fitting direction, the cover motion stopper is still engaging with the engaging surface of the plug in the state in which the plug is on the way to be removed, and thus the cover cannot be separated from the fuse storage section. In other wards, unless the plug is completely removed from the projecting wall to bring out of conduction completely, the cover cannot be removed from the fuse storage section, thereby ensuring that replacement of the fuse in the state of conduction is prevented.
The third aspect of the present invention is a breaker apparatus as set forth in Aspect 1 or Aspect 2, wherein the engaging surface is overhanging from the top surface of the lug toward the cover so as to engage with the cover motion stopper formed on the upper surface of the cover.
According to the third aspect of the invention, since the engaging surface overhanging from the top surface of the plug engages with the cover motion stopper formed on the upper surface of the cover so as to hold the cover motion stopper and the portion holding the cover is exposed to the outside, the state of engagement can be checked visually.
The fourth aspect of the invention is a breaker apparatus as set forth in any one of the first to third aspects, wherein a projection is formed on either one of the engaging surface or the cover motion stopper for engaging with a hole formed the other one of those.
According to the fourth aspect of the invention, since the projection and the hole engages with respect to each other, the cover motion stopper is prevented from being slipped off along the back surface of the engaging surface, whereby the engagement between them are enhanced.
The fifth aspect of the invention is a breaker apparatus as set forth in any one of Aspect 1 to Aspect 4, wherein a engaging portion for engaging with the surrounding wall of the breaker body to prevent the cover from being disengaged.
According to the fifth aspect of the invention, since the cover is engaged at both ends by engagement with the engaging surface of the plug and with surrounding wall of the breaker body by means of the engaging portion, disengagement of the cover 40 due to inclination thereof can be prevented.